Process and apparatus for reducing pulp



Feb. 12, 1929. 1,7021230 Y L. T. MURPHY PROCESS AND APPARATUS FOR REDUCING PULP Filed March 18, 1925 2 Sheets-$heet l ATTORNEY Feb. 12, 1929. 1,702,230

L. T. MURPHY PROCESS AND APPARATUS FOR REDUCING PULP Filed March 1 1925 2 Sheets-Sheet III ATTORNEY Patented Feb. 12, 1929.

UNITED STATES PATENT OFFICE.

LLOYD T. MURPHY, OF FRANKLIN, OHIO. V

PROCESS AND APPARATUS FOR REDUCING PULP.

Application filed March 18, 1925. Serial No. 16,268.

This invention relates to improvements in process and apparatus for reducing pulp, in which the processes of reduction are continuous, without interruption for charging, dumping and cleaning portions of the apparatus, as the stock breaker or heater which in the common type of apparatus become clogged with foreign materials contained in the raw stock. I

The main object attained in the invention consists in means associated with a stock beater or breaker for effecting separation from the mass of stock, in process of reduction in the apparatus, of heavy foreign substances, as fragments of metal, rock, glass, etc., which are found in various degrees in old paper and rag stocks, and which separate from the pulp mass and settle in the beater tub unless otherwise removed.

The common practice is to interrupt production at frequent intervals and remove the accumulation of such foreign substances by shoveling the same manually from the beater tub, then recharging the beater and continuing reduction until the apparatus again becomes clogged and reduction of the pulp stock is interfered with by the irreducible foreign matter accumulated in the bottom of the tub, when production is again interrupted while the beater tub is emptied'and cleaned, production and interruption for removing the junk, thus following one another with greatly retarded output.

A further important advantage attained by the improvements of my invention consist in uniformity of grade of production, both over reduction and under reduction of the pulp stock being avoided by the means provided for separating the finished stock, i. e., the part that has been reduced to the required state of fineness, continuously from the mass of stock in process of reduction, and thus preventing over disintegration of fibrous materials which make the finer grades of pulp. Under-reduction of the coarser materials cannot result because all the stock is continuously in process of reduction by hydration and the action of the beater thereon until the required state of fineness is arrived A further object attained in my invention consists in the elimination of certain units of apparatus required in ordinary reduction systems, as the settling trough and wet machine or stock thickener, and the intermediate pumps and connections for moving the stock from one unit to another. The economies effected in the firstcost of the improved apparatus, in maintenance, space saving and operating power amount to a very material item in reduced cost of production.

While the preferred use of my invention is with a continuous reduction apparatus, it will be obvious from the illustrations 'of the accompanying drawings and the detailed specification that the invention is also applicable to ordinary, or non-continuous stock heaters. As applied to this latter type of apparatus, the time and labor-saving features consisting in the means for removing the foreign substances from the apparatus without interrupting production are highly important.

In the drawings, which are here furnished to illustrate an application of my invention in one form:

Fig. 1 is a plane view in section on line 11 of Fig.3 of a reduction apparatus having my invention applied thereto;

Fig. 2 is'a cross sectional view and a detail in elevation taken on line 2-2 of Fig. 1;

Fig. 3 is a longitudinal sectional view taken on line 3-3 of Fig. 1;

f lFig. 4 is a detail of the perforated back- As here shown, the reduction apparatus consists of the beater tub I which is of the conventional type except that the tub is shown asbuilt in concrete under the floor line .2, thus to dispose of the main bulk of the apparatus from floor space; the conventional type of midfeather 3 and beater roll 4; the perforated backfall 5, and chest 6 for separatin and discharging finished pulp, being of wel known special construction.

The means for separating and removin heavy foreign substances from the beater tu consist in a pit 7 sunk below the beater tub, ports 8, 9 and 10 in the bottom of the tub being provided to permit the heavy foreign substances to pass from the tub into the pit, the bottom wall 11 of the pit within the plane of the tub, as best shown in Fig. 2, being inclined to cause the foreign material to move by gravity toward the lowest point 12 of the pit within range of a bucket conveyor 13 which acts to scoop it up and deliver the same into a dump box 14 which, as here shown, is supported at a higher elevation than the stock beater.

In the dump box the heavy substances, as fragments of iron, glass, stone, etc., sink to the bottom lighter materials that float in water overdow the box into-a trough 1516, arranged at right angles one to the other, and leading to a save-all 17 supported in a chest 18, which may be of any suitable construction, to salvage any pulp stock remaining in the water returned from dump box 14:,

such material being returned to the stock beater through a conduit 19. To minimize waste by salvaging all usable pulp material from the dump box, a pipe line 25 is con nected to the bottom of dump box 14: for

flushing the box upward with fresh water,

thus causing any pulp stock in the box to overflow the box into trough 15-16.

A'pipe 20 connects the screen chest 18 with pit 7 and acts to return the excess of water to the pit. A spillway 21 is provided in pipe the detail arrangements of the apparatus to suit variable conditions of pulp reduction.

Another such modification consists in a gate valve 23 disposed as illustrated in Fig. 2 in the channel leadingfrom the beater tub to pit "l, the valve being adapted to regulate the opening of the channel to any desired extent to prevent too free movement of water from the beater tub to the pit.

lhe backfall 5 is of the perforated type, illustrated in detail Fig. l now well known in this art, which acts to separate finished pulp under the force of action on the mass of stock of the beater roll l, and causes the same to be delivered into chest 6 from which the stock is delivered to a chest for finished pulp by a pipe 24:. 1

Operatin connection between the heater power mechanism and the chain conveyor may be arranged in any suitable manner, the arrangement here shown consisting of a pulley 26 on the beater roll shaft and a countershaft pulley 27 connected by a belt 28, the counter-shaft 29 being connected to the conveyor by means of chain sprockets 3030,

' idler sprockets 31 being employed to spread the upper course of the conveyor sufficiently to clear the dump box 14. In its lower course, the conveyor drags over a guard or doctor 32 which acts yieldingly to adapt the movement of the conveyor buckets to the accumulated foreign substances in the bottom of the it. D From the foregoing detailed description and the accompanying illustrations, it will be seen that the reduction processes can be moaaaa carried on indefinitely without interruption, that delivery of finished pulp will be continuous, that both over and under reduction Wlll be avoided, that there will be a minimum of waste and increased output.

Having described my invention, I claim 1. An apparatus for reducing pulp including in combination with a stock beater, means for removing fine pulp from said heater, a space communicating with the beater tub adapted to contain stock in process of reduction and for collecting foreign materials separated from the stock, means operable coincident with the operation of the heater for removing the foreign materials together with pulp adhering thereto from said space, and means for directing a stream of water on the foreign materials so removed whereby to return the pulp adhering thereto to the beater.

2. An apparatus for reducing pulp including in combination with a stock beater, means for removing fine pulp from said beater, a pit opening from the bottom of the beater tub for receiving foreign materials separated by gravity from stock in process of reduction, a conveyor operable in the pit for removing said foreign materials, and means for directing a stream of water on said materials removed by the conveyor for removing adhering pulptherefrom.

3. In a reduction apparatus including in combination with a stock beater, a pit at a lower level than the beater tub, an opening in the bottom of the tub and a passage leading from said opening to the pit whereby heavy foregin substances will gravitate from the tub into the pit, means, as an endless conveyer, for removing the foreign substance from the pit, a receptacle adapted to reveyor, for removing the foreign substance means to cause salvagable pulp stock to overflow said receptacle and to be returned to the stock beater, a pipe for returning water from said receptacle to said pit, and means to discharge water from said pipe over the foreign substances carried upwardly by said conveyor.

4:. Apparatus for reducing old paper stock, and the like, and for removing therefrom the heterogeneous and conglomerate assortment of miscellaneous junk, such as cans, metal parts, wire, rocks, glass parts, etc., which is found therein, which comprises, in combination, a stock beater, having means for reducing the paper stock and an unobstructed opening through which the said junk may pass by gravity into-a collecting pit, and a'conveyor operable upon the junk passing into said collecting pit for removing the said junk from said pit.

5. Apparatus for reducing old paper stock, and the like, and for removing the heterogeneous and conglomerate assortment of miscellaneous junk, such as cans, metal parts,

wire, rocks, glass parts, etc., which is found therein, which comprises in combination, a stock beater comprising a stock-circulating vessel, a heater roll and cooperating back-fall therein for reducing the said paper stock, said vessel having an unobstructed opening in the bottom thereof in communication with an i11- clined passage, both said opening and passage being of generous proportions, to permit tree passage therethrough of unk liberated from the paper stock within the circulating vessel, a pit into which said passage discharges the said junlr, and a conveyor operable within the said pit for removing therefrom the junk passing into said pit.

6. Apparatus for reducing old paper stock, and the like, and for removing the heterogeneous and conglomerate assortment of miscellaneous junk, such as cans, metal parts, wire, rocks, glass parts, etc., which is found therein, which comprises in combination a stock beater having means for reducing the paper stock and an unobstructed opening through which the said. junk may pass'by gravity into a collecting pit, a conveyor for removing the collected junk from said pit without interrupting the operation of the stock beater, a receptacle into which said conveyor discharges, and means within said receptacle for recovering fibrous material carried thereinto along with the junk,

7. Apparatus for reducing old paper stock,and the like and for removing the heterogeneous and conglomerate assortment of miscellaneous junk, such as cans, metal parts,

wire, rocks, glass parts, etc., which is found therein, which comprises in combination a stock beater having means for reducing the paper stock and an unobstructed opening through which the said junk may" pass by 40 gravity into a collecting pit, a conveyor for removing the collected junk from said it without interrupting the operation of t e stock beater, a receptacle into which said conveyor discharges, and means for flushing the junk within the said receptacle for recovering fibrous material carried thereinto along with the junk.

8. Apparatus for reducing 01d paper stock, and the like, and for removing the heterogeneous and conglomerate assortment of miscellaneous junk, such as cans, metal parts, wire, rocks, glass parts, etc., which is found therein, which comprises in combination, a stock beater having a stock-circulating vessel, means therein for reducing the paper stock, said vessel having an openin in the bottom thereof through which the sai junk may pass by gravity, an inclined passage connected to said opening, a collecting pit located to one side of the stock-circulating vessel into which said passage discharges, the construction being such that junk separated from the paper stock within the beater will freely pass by gravity through the said opening and passage 5 into the said pit, and a conveyor operable within the said pit for removing therefrom the uni: passing thereinto.

In testimony whereof, I afiix my signature.

LLOYD T. MURPHY.

CERTIFICATE OF CURREGTIOND Patent No, 1,702, 230.

Granted February 12, 1929, to

LLOYD T, MURPHY,

it is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows;

Page 2, line 106, strike out the syllable and words veyor, for removing the foreign substance" and insert instead the syllable and words "celve said substance from the conveyor,; and that the said Letters Patent should be read with this correction therein that the same may eonlorzn tn the record of the case in the Patent Office,

Signed and scaled this 19th day of March, A, D, 1929.

(Seal) M l. Moore, Acting Commissioner of Patents.

CERTIFICATE OF CQRRECTION.

Patent No. 1,702,230. Granted February 12, 1929, to

LLOYD T. MURPHY.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, line 106, strike out the syllable and words "veyor, for removing the foreign substance" and insert. instead the syllable and words "ceive said substance from the conveyor,; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

1 Signed and sealed this 19th day of March, A. D. 1929.

M. J. Moore,

(Seal) Acting Commissioner of Patents. 

